Conventional golf balls include several dimples on their cover, e.g., to improve ball flight by providing lift to the ball and promoting establishment of a turbulent air flow (to reduce aerodynamic drag). While many different dimple types exist (e.g., different sizes, shapes, cross sectional profiles, etc.), most conventional dimples on conventional golf balls have a generally round perimeter or edge shape (e.g., a round appearance for the dimple edge or perimeter when viewed from above).
Also, conventional round dimples of the types described above also typically have a cross sectional profile such that the majority of the surface of the dimple (i.e., the areas of the dimple surface away from the very edge) corresponds to the arc of a circle. In other words, a conventional dimple will have the majority of its surface corresponding to a portion of a sphere. FIGS. 1A and 1B help illustrate this conventional design. As shown in FIG. 1A, in a conventional golf ball 10 design, all of the dimples 12 on the ball 10 (only a portion of which are shown) are arranged such that radial lines R running from the center C of the overall ball structure 10 will also intersect the center Cd of each dimple. In other words, a radius R through the center C of the golf ball 100 will align with a radius Rd of the spherical shape from which the majority of the dimple surface Sd is formed.
FIG. 1B illustrates an individual conventional dimple 12 in greater detail (e.g., like the dimple 12 in the upper right portion of FIG. 1A). As shown in this figure, the center Cd of the dimple surface Sd (as shown by the location of the dimple tangent line Td) and the ball tangent line Tb centered over that dimple (assuming that the ball surface S is a perfect sphere without dimples) are aligned such that a single line passes through both the ball center C (shown in FIG. 1A and not in FIG. 1B) and the dimple center Cd at the ball and dimple tangent points. In other words, in this conventional ball design 10, the dimple(s) 12 are symmetrically oriented such that the dimple radius Rd (through its center point Cd) extends in the same direction as a radial axis R from the dimple center Cd and through the ball center point C. Notably, in this illustrated arrangement, the dimple tangent line Td is parallel to the ball tangent line Tb. This highly symmetrical and aligned type of dimple structure, as used herein, may be referred to as a “tangential dimple” or a “conventional dimple.” Often, all dimples on a given golf ball structure will have this tangential or conventional dimple orientation.
While these conventional dimple structures provide known aerodynamic effects on golf ball structures, there is room for improvement in the art. For example, by providing non-uniform dimple designs, dimple profiles, and dimple patterns on a golf ball, the lift, drag, and other aerodynamic properties of a golf ball structure can be altered and controlled.